1. Alan Alda — who would later play the Republican rival in the election to replace President Bartlet — was originally considered for the role of Bartlet, along with Sidney Poitier and Jason Robards. Poitier was actually the first choice, but his fee was too high.

2. Bradley Whitford was originally offered the part of Sam Seaborn, who the show was originally conceived to revolve around (it was when Rob Lowe realized that Seaborn would forever be an ensemble player instead of the lead that he decided to ditch the show).

3. Eugene Levy was considered for the role of Toby Ziegler, which would’ve been super weird.

4. The Oval Office used in “The West Wing” was the same Oval Office used in the movies Dave and The American President (also written by Aaron Sorkin).

5. This Scene from season one, in which C.J. Cregg lip syncs “The Jackal,” was written into the episode because Allison Janney was doing the same thing on set to entertain the crew and Sorkin liked it so much he added it to the show.

6. The episode, “Crackpots and These Women” was about a day each year in the Bartlet White House in which special interest groups who wouldn’t otherwise be heard were granted access. The tradition derived, according to Leo McGarry, derived from a two-ton block of cheese granted to President Andrew Jackson and left in the White House foyer. The cheese remained in the foyer for two years, before Jackson figured out what to do with it. He invited 10,000 people to the White House, and they ate it all in under two hours. The story is absolutely true (although, the cheese only weighed 1,400 pounds). Mental Floss has a fascinating write-up. It was also the episode that featured Nick Offerman.

7. The character played by Bradley Whitford, Josh Lyman, got his name from a similarly situated character in the Doonesbury comic strip. Either that, or a character from 1776. Or both.

8. The relationship between C.J. Cregg and Danny Concannon was actually based on the real-life relationship between Clinton White House Press Secretary Dee Dee Myers (who was a consultant on “The West Wing”) and her husband, New York Times reporter Todd Purdum.

10. You may recall that Danny, mistaking C.J.’s love for Goldfish crackers, gave her an actual goldfish.

Throughout the series, the decorations in that goldfish bowl changed to fit the theme of a particular episode.

10. Janel Moloney, who played Donna Moss, originally auditioned for the role of C.J. Cregg. Her Donna character was not intended to be a series regular. In fact, she was only credited under “guest appearance” for the entire first season of the show. Sorkin elevated her because of her chemistry with Bradley Whitford’s Josh Lyman.

11. Josh Malina is a lifelong friend of Aaron Sorkin who has been in everything Sorkin has ever done (except, so far, “The Newsroom”), which is what made him such a natural fit to replace Sam Seaborn when Rob Lowe left. However, Dermot Mulroney, Judd Nelson, Macaulay Culkin, and Jon Cryer were also considered for the part.

12. Danica McKellar had a recurring role on the show as Elsie Snuffin. Elsie Snuffin is the real name of Kayla Blake, who played Kim on Sorkin’s “Sports Night.”

13. This is an iconic photo of JFK during the Cuban Missile Crisis.

This is a screengrab of President Bartlet in the opening credits of “The West Wing.”

14. Remember last year, when virtually the entire “West Wing” regular cast got together to make a political ad for Mary McCormick’s sister, Bridget Mary1 McCormack, who was running for Michigan Supreme Court?

She won.

15. I have absolutely no recollection of a 2003 TV series, “Mr. Sterling,” starring Josh Brolin has an independent California Senator. However, the show came from Lawrence O’Donnell, the exec producer on “The West Wing,” and it may or may not have existed in the same universe as “The West Wing,” but the President of “Mr. Sterling’s” universe was President Bartlet. The series only lasted 10 episodes before it was cancelled, so there was never a ripe opportunity for a cross-over episode.

16. See the “Bartlet for America” poster here:

That’s funny because that’s the set for Studio 60 on the Sunset Strip.

17. Aaron Sorkin is most often credited for the popularization of the “walk and talk,” which became a big deal during “The West Wing.” It was, in fact, director Thomas Schlamme who incorporated the walk-and-talk, first in “Sports Night,” and heavily in “The West Wing,” as a way to bring a little action to Sorkin’s dialogue-heavy scripts. Sorkin has since used it in “Studio 60” and “The Newsroom.”

18. The budget for each episode of “The West Wing” was $6 million. For comparison’s sake, the first season of “Game of Thrones” cost $60 million for 10 episodes, or $6 million per ep.

19 Hey! Remember the crushing death of President Bartlet’s Secretary, Mrs. Landingham? It was so upsetting that, in real life, a San Francisco assemblyman, Kevin Shelley, adjourned a session of the California Congress to grieve for her, calling Landingham a “great American” whose “contributions to the nation were too numerous to count.” Shelley resigned from his position in 2005 under a cloud of scandal.

20. One pop psychologist claims that Aaron Sorkin is better than Shakespeare by virtue of having a higher order theory of mind. I won’t try to explain that, but the article is equally bonkers and interesting.

Dustin is the founder and co-owner of Pajiba. You may email him here, follow him on Twitter, or listen to his weekly TV podcast, Podjiba.